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A252534 Number of (2+2) X (n+2) 0..3 arrays with every 3 X 3 subblock row and diagonal sum equal to 0 2 3 6 or 7 and every 3 X 3 column and antidiagonal sum not equal to 0 2 3 6 or 7.

%I A252534 #8 Dec 04 2018 11:04:21
%S A252534 595,337,341,462,706,1000,1468,2420,3480,5240,8872,12880,19696,33872,
%T A252534 49440,76256,132256,193600,299968,522560,766080,1189760,2077312,
%U A252534 3047680,4738816,8283392,12157440,18914816,33081856,48563200,75578368,132224000
%N A252534 Number of (2+2) X (n+2) 0..3 arrays with every 3 X 3 subblock row and diagonal sum equal to 0 2 3 6 or 7 and every 3 X 3 column and antidiagonal sum not equal to 0 2 3 6 or 7.
%H A252534 R. H. Hardin, <a href="/A252534/b252534.txt">Table of n, a(n) for n = 1..210</a>
%F A252534 Empirical: a(n) = 6*a(n-3) - 8*a(n-6) for n>10.
%F A252534 Empirical g.f.: x*(595 + 337*x + 341*x^2 - 3108*x^3 - 1316*x^4 - 1046*x^5 + 3456*x^6 + 880*x^7 + 208*x^8 + 128*x^9) / ((1 - 2*x^3)*(1 - 4*x^3)). - _Colin Barker_, Dec 04 2018
%e A252534 Some solutions for n=4:
%e A252534 ..1..2..3..2..2..3....1..3..3..0..0..3....3..3..0..0..2..0....3..3..0..3..0..0
%e A252534 ..3..2..2..3..2..2....2..3..2..2..3..2....0..0..2..0..0..2....3..2..2..3..2..2
%e A252534 ..0..0..3..3..1..3....2..2..3..2..2..3....1..2..3..1..2..3....2..3..2..2..3..2
%e A252534 ..2..2..3..2..2..3....0..3..3..1..3..3....0..2..0..0..3..0....0..3..0..3..3..0
%Y A252534 Row 2 of A252532.
%K A252534 nonn
%O A252534 1,1
%A A252534 _R. H. Hardin_, Dec 18 2014